Any analysis on the climate impact of a data center should consider resource utilization and energy efficiency, in addition to power mix. Carbon emissions are a factor of three things: the number of servers running, the total energy required to power each server, and the carbon intensity of energy sources used to power these servers. A recent blog post by Jeff Barr outlines why using fewer servers and powering them more efficiently is at least as important to reducing the carbon impact of a company’s data center as its power mix.

A typical large-scale cloud provider achieves approximately 65% server utilization rates versus 15% on-premises, which means when companies move to the cloud, they typically provision fewer than ¼ of the servers than they would on-premises.1 In addition, a typical on-premises data center is 29% less efficient in their use of power compared to a typical large-scale cloud provider that uses world-class facility designs, cooling systems, and workload-optimized equipment.2 Adding these together (fewer servers used plus more power efficient servers), customers only need 16% of the power as compared to on-premises infrastructure. This represents an 84% reduction in the amount of power required.

This massive improvement in energy efficiency drives a huge reduction in climate impact because less energy consumed means fewer carbon emissions. The climate impact improvements get even better when you factor in that the average corporate data center has a dirtier power mix than the typical large-scale cloud provider. Large-scale cloud providers (AWS included) use a power mix that is 28% less carbon intense than the global average.3